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Dams challenge Atlantic salmon (Salmo salar) conservation, while hatcheries are a common but poorly evaluated recovery tool. We developed a spatially explicit smolt survival model for the Penobscot River, Maine, USA, population. By partitioning survival through dams (with flow dependency), free-flowing river reaches, and the estuary (with dam dependency), the model quantified how these factors influenced the number of fish entering the ocean. Given historical impounded conditions, 74%–22% of hatchery smolts released entered the ocean annually from 1970 to 2012. Of 19.7 million smolts stocked, 7.7 million entered the ocean (39%). Survival was most variable at dams (range 95% to 63%), followed by in-river (range 98% to 70%) and estuary (range 88% to 82%). Overall, lower-river stocking sites resulted in significantly higher numbers at ocean entry because of fewer dam encounters and shorter migrations. Higher flows also resulted in reduced losses. By reconstructing these freshwater and estuary dynamics, the model provides a more accurate estimate of ocean recruitment annually and can be used for scenario planning of future stocking locations relative to predicted flows while being adaptable to new survival rates. [ABSTRACT FROM AUTHOR]

Diadromous species historically dominated the freshwater fish community in coastal northeastern United States rivers. As these fishes declined in concert with sweeping alterations to the region's waterscapes, so too did their utility, visibility, and relevance to each passing human generation. Due to their historically iconic status, we used endangered Atlantic Salmon Salmo salar as a springboard in our study of attitudes and values about fish in the context of modern human connections to places and the water bodies therein. We surveyed Maine residents about their connections to local water bodies and fish populations. Respondents were generally apathetic toward fish overall, but they valued the water bodies in their home turf as escapes from daily stressors. We explored this finding as it relates to motivating behavior and redefining contemporary baselines of water body health, which may help restore Maine's diadromous fish community to a local and regional treasure and commodity. Understanding the facets of sense of place, including satisfaction and attachment, can ultimately help to reframe how we communicate with the public about acting on behalf of the places they care about that overlap with important fish habitat. [ABSTRACT FROM AUTHOR]

Presents a study that documented estuarine predation by an immature striped bass upon an Atlantic salmon smolt that had been tagged with an ultrasonic transmitter on the Narraguagus River in Maine. Potential confounding effects that fish predation can have upon a telemetry study; Movements of immature striped bass in the river system; Decline of the salmon abundance in the river since the mid-1980s.